Design engineers include thin film resistors (TFR) in integrated circuit (IC) designs. Parameters that are controlled during the design stage include the sheet resistance of the TFR and the temperature coefficient of resistance (TCR), which characterizes the change in sheet resistance per unit change in temperature.
Controlling the sheet resistances and TCRs of TFRs on different layers of an IC is complicated, because temperature processing of a subsequently deposited layer can affect the sheet resistance and TCR of a previously deposited layer.
Improved TFR integration methods are desired